Inspect sealed spawn packaging, its label, lot identity, production date, integrity and visible abnormalities. Appearance alone cannot establish purity or performance. Do not open or deliberately smell suspect spawn; keep it separate and contact the supplier.
Ask for species- and strain-specific storage conditions and the validated use-by period. There is no single age limit or refrigeration rule for all mushroom spawn. Record transport conditions and use the supplier protocol rather than a universal 30-day rule.